Tecfluid MT03F - Manual (Page 22)

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7.5.1 Cut off
A cut off flow rate can be programmed, that means, the flow rate below which the flow
rate indication will be zero. This can avoid reading errors in the lower zone of the working
range.
The configuration of this filter can be very useful in the cases where the flow rate readings
have some instability (due to air bubbles, solids in suspension, etc).
Only the flow rate indication of the display and the analog output are affected by the filter.
The relay output and the totalizer act according to the instant flow rate. Selecting a filter
with a longer or shorter integration time will provide more or less stable readings and will
also affect the response time to small variations of flow rate.
The integration time is selected in seconds, with a minimum value of 0 and a maximum
value of 25 seconds. For example, with an integration time of 15 seconds, the display will
indicate the flow rate reading of the average flow rate over the last 15 seconds from the last
update of the display. This does not mean that the display is refreshing its data every 15
seconds. The display shows a new value several times per second, indicating an average
of the flow rate values of the last 15 seconds.
When there is a sudden variation of the flow rate then the filter should react as fast as
possible to give a correct reading of the new value. For this, the filter controls the deviation
of the instant flow rate with respect to a reference for each reading. If this deviation
exceeds the 25%, the filter will stop acting, indicating the instant value, and will start again
the filtering process.
7.6 Outputs
This screen allows to program the three outputs of the instrument: Relay 1, Relay 2 and
analog output (4-20 mA).
7.5.2 Damping
The converter has an adaptive filter (damping) to provide stable flow rate and analog
output readings in the presence of continuous flow rate fluctuations.